The present invention is directed to improvements in article detection systems, and more particularly to systems for optically detecting and counting such articles.
In the commonly assigned Hinds Pat. No. 3,964,041 there is disclosed an article detection system and method which was described as particularly useful in counting container ends. As indicated in that patent, it had been the practice in the production and packaging of articles, such as container ends, to package an approximate number of ends based on the assumption that a given number of nested ends would fit within a certain dimension. Since that assumption was only an approximation for the reasons indicated therein, it was the practice to add a "few extra" ends to insure that the package stack contained the minimum number. At the rate at which such articles were being packaged, about 300-500 ends per minute, the number of "extras" resulted in substantial additional costs.
The system and method disclosed in the aforementioned Hinds Pat. No. 3,964,041 was designed to provide an accurate system for counting the number of ends to permit packaging a desired number. While the system and method disclosed in said patent was a quantum improvement over previous techniques for approximating the number of articles in a package, that system in practice, did not achieve the exacting standards of accuracy for which it was designed.
It would be highly desirable, therefore, to minimize inaccuracies and errors in article detection and counting systems, and to provide a system which minimizes chances of error both in the detection of the articles to be counted and in the evaluation and processing of signals representative thereof.